This invention relates to a system for dispensing potable liquids, such as, for example, draft beer, and to a dispensing apparatus therefor.
The application of a dispensing device to draft beer creates a difficult problem since carbonation of beer is quite sensitive to temperature of the draft beer product. Most other carbonated beverage products can be handled by apparatus that will successfully handle draft beer. Accordingly, as draft beer is the most difficult potable beverage to handle, the application of the present invention to the draft beer product will be described as the exemplary potable beverage.
There are currently two methods of dispensing draft beer. One method involves the use of what is known as the direct-draw box. The direct-draw box, in essence, is a small refrigerator using an external forced air cooled condensing unit and an internal evaporator cooling coil with a fan. The direct-draw box includes a beer tap, usually mounted on a draft beer arm or tower, and the necessary valves and tubing required to tap the beer container or keg and to remove the beer, as well as means for pressurizing the keg with pressure regulated CO.sub.2. Direct-draw boxes usually contain one keg of beer but amy even have the capacity to contain up to four kegs.
In operation, kegs are taken from refrigerated storage and placed in the direct-draw box, tapped and pressurized whereby dispensing may continue until the supply of beer within the keg is exhausted. The direct-draw box has a number of disadvantages, the principal one being the amount of space required. Typically, a minimum of five square feet is necessary. In addition, access to the box is required which can preclude the use of the box in some existing establishments. Even in newly constructed premises or those premises undergoing major renovation, it is desireable to minimize the bar area and maximize the seating area. Thus use of floor storage space for beverage storage is undesireable.
Secondly, bringing the keg, which weighs about 150 pounds, from the storage area to the draw box is a significant task. Moreover, when the keg arrives at the draw box, it usually has to be lifted about six inches form the floor to place the keg in the unit. Many establishments employ female staff, and occasionally an establishment has exclusively female staff. In such establishments, the physical demands of the direct-draw box method may also preclude its use.
In addition, there is a fairly substantial capital cost to purchase a direct-draw box unit as well as the ongoing cost of maintaining two fans, a refrigeration compressor and temperature control. Furthermore, if any of these elements should fail, or if the condenser becomes plugged, beverage sales are lost until the unit is repaired and operating again. In addition, the unit requires energy to operate and, certainly during the cooling season, heat generated by the direct-draw box unit has to be removed from the establishment by air conditioning.
The second conventional method of dispensing draft beer is by means of a remote system. This method permits an operator to dispense beer directly from a remote refrigerated storage area to the tap at the bar. Typically, the refrigerated storage area is a walk-in cooler. The remoteness between the tap and the keg can be as little as a few feet to distances of 150 feet. However, with draft beer it is important to recognize that if the beer in the lines from the walk-in cooler to the tap in the bar rises above 5 degrees Centigrade (41 degrees Fahrenheit) the beer will "break". That is, the CO.sub.2 dissolved in the beer will break out and form vapor pockets in the liquid beer. When such beer arrives at the tap, it issues as pure foam. Foam will continue to be dispsensed until the beer line is re-cooled by fresh cold beer from the walk-in cooler. The amount of waste can vary from a few glasses in an installation with a short line to many gallons in an installation with a very long line. For economic reasons, it is therefore essential that the beer in the line be kept cooled to around 3 degrees C. (38 degrees F.) and it will be further recognized that with shutdowns, such as overnight, on Sundays, or holidays or combinations of any of these, maintaining the beer at 3 degrees C. cannot be done by insulation alone.
The existing method of providing remote draft beer involves running a number of tubes in parallel relationship inside a flexible foamed plastic tube which acts as an insulator. The number of tubes inside the insulating tube is generally a minimum of four--one for coolant supply, one for coolant return, and the other two available for beer. Alternatively, one of the other two may be used for beer while the other is available as a return line for cleaning the beer line. Standard commercial systems are available with up to six beer lines in addition to the two coolant lines. The known system also involves a condensing unit, a refrigerant to coolant (usually glycol) heat exchanger, a glycol sump, a glycol pump, and a glycol temperature controller.
Such a system has some advantages over the direct-draw system in that little space is required in the bar area and that kegs do not have to be transported from a storage area to the bar area. It does, however, suffer from various disadvantages. At best, the known remote system depends on line contact between the circular cooling tubes and the beer line. Thus, where a large number of beer lines are involved, some will not even have line contact. This situation will involve inefficiencies since some of the lines will have to be cooled by first having the glycol cool the air inside the insulating tube and then having the air cool the beer lines.
As with the direct-draw box there is also the relatively high capital cost of the known remote system, since it involves an additional refrigeration condensing unit. Furthermore, the cost of operating the known remote system is high since it includes its own energy cost and ongoing maintenance costs. Of course, the problems of heat removal remains and, with the additional components, the problem of ultimate failure continues. As a result of these considerations, the loss of business until repairs are effected is also a problem with the known remote system. In addition, space must be found to locate the condensing unit.
The present invention overcomes the above-mentioned disadvantages of the current methods and apparatus for dispensing draft beer by providing a dispensing system and apparatus therefor of extreme simplicity, utilizing only one moving part, i.e., the pump, which has a long record of reliable and trouble-free operation and utilizes no secondary controls.
A remote system typically involves a beverage supply which is both pressurized and pressure regulated, as well as at least one beverage tap. The present invention focuses in part on a method and apparatus for delivering beverage from a typical pressurized and pressure regulated source to a remote tap.
It is an object of the present invention to overcome the above disadvantages by providing a simple and relatively inexpensive system for dispensing beverages and a dispensing apparatus which incorporates a much more efficient heat transfer design.
According to one broad aspect, therefore, the present invention relates to a system for dispensing beverages including, in combination, (a) at least one beverage supply tube connected to a pressurized source of supply for the beverage; (b) cooling means connected to a pump which, in turn, is connected to a cooling manifold, the supply tube passing through the manifold to a dispensing tap; (c) a pair of coolant supply and return tubes substantially concentrically disposed within one another and each having one end located within the manifold and the remaining end located adjacent the tap, the supply tube passing through the coolant supply tube and being connected to the tap; and (d) a pair of inlet and outlet ports in the manifold connected, respectively, to the coolant supply and return tubes as well as to the pump and the cooling means.
According to another broad aspect, the present invention relates to apparatus for dispensing beverages, including, in combination, (a) at least one beverage supply tube connected to a pressurized source of supply of the beverage; (b) cooling means; (c) a pump connected to the cooling means; (d) a cooling manifold connected to the pump; (e) a dispensing tap, the supply tube passing through the manifold to the tap; (f) a pair of coolant supply and return tubes substantially concentrically disposed within one another each having one end located within the manifold and the remaining end located adjacent the tap, the supply tube passing through coolant supply tube and being connected to tap; and (g) a pair of inlet and outlet ports in the manifold connected, respectively, to the coolant supply and return tubes and to the pump and the cooling means.